Method of cleansing dishes



p 9 5 D. K. FERRIS I 2,385,264'

METHOD OF CLEANSING DISHES Sept. 18, 1945. D. K. FERRIS METHOD OF CLEANSING DISHES 4 Sheets-Sheet 3 Filed Oct. 16, 1940 Sept, 18, R945. D. K. FERRIS METHOD OF CLEANSING DISHES Filed Oct. 16, 1.940 4 Sheets-Sheet 4 I m w the washing zone, later to be Patented Sept. 18, 1945 -UNITED STATE 2,385,264 METHOD OF CLEANSING DISHES Donald K. Ferris, Dayton,

eral Motors Corporation, Dayton,

poration of Delaware Application October 16,1940, Serial No. 361,439

8 Claims.

This invention relates to a method of cleansing dishes.

This application is a continuation in part of my copending application S. N. 84,504, which was filed June 10, 1936, and which has now mat-gzed into Patent No. 2,314,332 dated March 23,

An object of this invention is to provide a method of cleansing dishes by which accumulation of lime deposit on the dishes is prevented.

Another object of this invention is to provide a method of cleansing dishes in which the hardening or setting of certain foods on the dishes is prevented.

My method of washing dishes is particularly useful for use in any dish washing machine where the same dishes are repeatedly washed and dried without being rubbed by toweling or the like. Heretofore the repeated washing of dishes in dish washing machines in this manner has tended to build up a coating of lime and other insoluble deposits on the dishes by the repeated evaporation of mineral-containing water on the dishes during the'drying operation. This evaporation of water from the dishes allows the minerals in solution in the water to be deposited on the dishes with an accompanying reaction tending to create insoluble films on the dishes Repetition of such a cycle from day to day eventually builds a very undesirable coating on the dishes which can only be removed by special treatments. My method overcomes this undesirable result by depositing a thin invisible film of soluble substance on the dishes during the last rinsing and evaporating operation, so that this film of soluble substance may be washed ofi at the next washing operation. Consequently, according to my method, no hard crust is built up on the dishes even by the repeated washings practiced in the home, hotel or the like.

. While I contemplate many methods of applying the thin film of soluble substance to the dishes, at present I prefer to accomplish this by allowing a small quantity of soapsuds to remain in mixed with the final rinse water, so that when the adhering rinse water is evaporated from the dishes during the drying operation, a thin invisible film of soap is deposited on the dishes for subsequent removal during subsequent washing operations.

Another objectionable feature of present dish washing machines is that certain foodsubstances are set on the dishes by the application of hot soapsuds durin the first washing operation. The food particles left on the dishes are of divergent Ohio, assignor to Gen- Ohlo, a corcharacteristics so that certain foods, such as eggs,

Q flour paste andthe like, are set on the dishes by an initial application of hot wash water, and thereafter these substances cannot be removed without 'vigorous rubbing of the dishes. Other substances require the application of hot soapsuds in order to remove them from the dishes without vigorous rubbing action. Dish washing machines cannot conveniently be provided with any rubbing device. Consequently when the usual hot soapsuds are applied to the dishes in a dish washing machine, in an effort to remove those substances requiring not wash water, the particles Of egg, flour paste and the like are set on the dishes. Under these circumstances, the wash- I ing operation generally must be followed by hand washing in order to remove such set particles from the dishes. My method overcomes this objection by initially soaking the dishes with a cool soap solution for a sufllcient time to soften the particles of egg, flour paste, etc., after which hot soap wash can be applied to clean the dishes thoroughly without danger of setting the albuminous soil on the dishes. Temperatures much above human body temperatures tend to set albuminous substances on the dishes, and therefore the cool soap wash preferably should be below body temperature. The hot soap wash should be sufficiently hot to melt. animal fats, and I prefer a temperature of or more.

While I contemplate many ways of applying the relatively cool soap wash and the subsequent relatively hot soap wash to the dishes, I i now prefer to accomplish this by maintaining the dishes in an elevated cleansing zone and by introducing the soap and a small amount of relatively cold water in a liquid retaining zone below the dishes. This soap wash is whipped to apply a mist of cold soap wash to the dishes for a sufficient time to soak the food particles thoroughly, after which I introduce a relatively large amount of hot water in the liquid retaining zone there to mix with the cold concentrated soap wash to produce a relatively hot soap wash which is then applied by whipping same upon the dishes from the liquid retaining zone.

If desired, the relatively cool soap wash may be applied to the dishes preferably below human body temperature and be gradually heated to a sufliciently high temperature to produce the cleansing operation of the hot soap wash.

In order that the application of my method to a dish washing machine may be more thoroughly understood, I describe the application -of my method to the washing machine illustrated in the accompanying drawings, although it is to be understood that such specific illustration is not intended by way of limitation to the particular machine illustrated but merely in order that my invention may be more thoroughly and generally understood.

While I have pointed out certain objects of my invention above, further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompa drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a sectional elevation of a washing machine embodying one form of the invention;

Fig. 2 is a fragmentary sectional elevation on line 2-2 of Fig. 3;

Fig. 3 is a front elevation as viewed from the right of Fig. 2;

Fig. 4 is a sectional plan taken on line 4-4 of Fig. 2;

Fig. 5 is a fragmentary sectional elevation through the receptacle containing the rinse water;

- Fig. 6 is a plan view illustrating the manner of constructing the switch and heating units for controlling and heating the liquid;

Fig. 7 is a sectional elevation on line 1-1 of Fig. 6;

Fig. 8 is an enlarged sectional elevation on line 8-8 of Fig. 6;

Fig. 9 is a top plan view of a slightly modified form of heating unit;

Fig. 10 is a sectional elevation taken on line liii0 of Fig- 9;

Fig. 11 is a fragmentary sectional elevation 11- lustrating the latch mechanism for securing the cover for the washing chamber in closed position with the magnet for releasing the latch shown in normal deenergized position;

Fig. 2 is a similar view showing the armature of the magnet in position to effect release of the latch when the armature becomes deenergized;

Fig. 13 is a part sectional elevation illustrating the drain for the dish washing chamber and associated parts;

Fig. 14 is a similar view showing the drain valve in closed position;

Fig. 15 is a diagrammatic view showing the electrical devices and the circuit connections therefor;

Fig. 16 is a plan view of one of the hinges for raising the cover of the machine when the latching means therefor is released;

Fig. 17 is a transverse sectional elevation through the hinge shown in Fig. 16;

Fig. 18 is a view in elevation of a modified form of the invention; and

Fig. 19 is a sectional elevation of another modiflcation.

The same reference numerals throughout the several views indicate the same parts.

My method may be practiced in the washing machine illustrated, which washing machine is more fully described and certain parts thereof claimed in my Patent No. 2,314,332 referred to hereinabove to which reference is made, if necessary for further disclosure.

The dishes It, to be washed. may be maintained in an elevated cleansing zone by the rack l'l placed in the container l3. This cleansing zone is above a liquid retaining zone I l in the lower part of the container l3. A cold concentrated soap wash may be introduced into the liquid retaining zone I by placing a suitable quantity of soap in the substantially accuses zone i4, together with a small quantity of cold water, which water may be introduced through the pipe 44 from suitable feeding and measuring receptacles hereafter to be more fully described. The relatively cool soap wash is whipped by the rotatable impeller II to create a mist of said cool soap wash which is applied to the dishes it for a sumcient time to thoroughly'soak and soften all of the food particles on the dishes. Thereafter a relatively hot soap wash is produced by introducing a relatively large amount of hot water through the pipe 44 into the none I where the hot water mixes with the cold soap wash to produce a hot soap wash. This soap wash, which stands at a higher elevation with respect to the impeller I5, is whipped by the impeller l5 and is thus applied to the dishes IS with more violence in a manner to remove the softened food particles from the dishes. During this washing operation, soapsuds are created in the container i3 and a certain portion of the suds is deposited on the dishes I! and throughout the upper part. of the container or cleansing zone. Thereafter the hot soap wash is drained from the zone ll through the outlet 2|.

The dishes are then subjected to a pro-rinse operation to remove a portion of the soapsuds while retaining another portion of the suds in the elevated. cleansing zone. This is accomplished by introducing a relatively small quantity of rinse water through the pipe 44 and whipping the same by the agitator l5 while the valve 20 remains open. Because of the low level of the rinse water around the agitator I 5, the rinse removes a portion of the soapsuds, together with any adhering food particles in the lower part of the elevated cleansing zone while retaining another portion of the suds on the upper part of the container.

After the pre-rinsing operation has terminated, the valve 20 is closed and a relatively large amount of rinse water is introduced through the pipe 44 and the same is whipped by the agitator I 5. This rinse water mixes with the retained portion of soapsuds to produce a rinse wash with a minute quantity of soap in it. The dishes are rinsed for a sufficient length of time to insure thorough removal of all soapsuds and adhering food particles and the rinse water is then drained by opening of the valve 20. The rinse water adhering to the dishes i8 is then evaporated from the dishes by creating a convection current of air through the container l3 through valve 20 and the partially opened top of the container. This causes a thin invisible and unobiectionable film of soluble substance to be formed on the dishes i6 because of the non-evaporation of the minute quantity of soap in the rinse water. This thin film of soluble substance may contain a small amount of minerals from the water, but the soap film prevents such minerals from adhering to the dishes, so that all of the adhering soap and minerals are subsequently removed during a later washing operation.

From the foregoing brief preliminary description, it is to be noted that I contemplate a "prewash" of relatively cool soap solution, followed by a "wash of relatively hot soap solution, followed by a pro-rinse, followed by a regular rinse" containing a minute quantity of soap, followed by evaporative drying with a consequent formation of a protective soluble invisible thin film of soap on the dishes.

The liquids are introduced into the liquid re taining zone ll preferably by liquid-holding and heatreceptacles are then tilted with a properly viously placed in the zone M, to create the cool in: receptacles 21, 29,- and 29, and these receptacles are in turn filled by liquid measuring containers 21a, 29a and 2911 which are tiltably. supported by the hinges 95. At the beginning of the washing operation the dishes l9 are placed on suitable racks I1, and water at placed in the receptacles 21a, 29a and 29a to the level 39, as indicated in Fig. 2. The level in these receptacles is equalized by side opening 39 in the partition walls separating the receptacles. These about the hinges 35, so that their respective water contents are discharged into the respective receptacles 21, 28 and 29. The water in receptacles 29 and 29 is then subjected to aheating operation by suitable electric heaters, hereafter to be more fully described, at such rate that the water in receptacle 28 is heated to the proper temperature during the prewashing operation, and the liquid in receptacle 29 is heated to its proper temperature during the pre-wash and wash cycles, so that it is ready for use immediately after the termination of the wash cycle. The heating operation preferably is combined with a syphonic action, hereafter to be more fully described, initiated by the creation of steam within the inverted containers or bells 29b and 29b. The result is that, after the receptacles 21a, 28a and 29a have been tilted, the correct amount of cold water is discharged from the receptacle 21 into the zone N, there to be mixed measured quantity of soap presoap wash and there to be whipped by the agitator l for a sufflcient length of time to thoroughly soak the food particles on the dishes l6. Dur n this pr-washing operation, the liquid in receptacle 28 is being heated, so that it is at the proper temperature when the pro-wash is to be terminated. At this time steam isproduced in the bell 28b to initiate a syphoning action of hot water from the receptacle 28 to the zone M. This water then mixes with the pre-wash soap solution and creates the hot soap wash which is then whipped by the agitator l5 for a suflicient length of time to produce the suds and tofore described. The valve 29 then is automatically opened and the wash solution is drained through the opening 2| into the receptacle 25 while soapsuds remain on the dishes "5 and in the elevated cleaning container l3. Thereafter a small amount of prerinse water is discharged from the receptacle 29 into the zone I4 there to be whipped by the agitator l5 while the valve 20 is maintained open. This pre-rins ng operation removes a the soapsuds while retaining another portion in the elevated cleansing zone. Thereafter the valve 20 is closed and the remaining major portion of liquid from receptacle 29 is introduced into the zone i4 through the pipe 44 and the dishes are subjected to the final rinse. This rinse mixes with the retained soapsuds to produce a rinse water containing a minute quantity of soap capable of producing the thin invisible film of soap. The subsequent drying evaporating cycle is accomplished by draining the rinse water through the opening 2! and allowing air to ass upwardly through the opening 2|, by convection, past the dishes I6 and out through the top of the container l3 through the now partially elevated cover i3a, as indicated by the dotted lines in Fig. 1.

If it is desired soapsuds during the be added to the washing machine to to retain a larger proportion of pre-rinse, a structure may catch the to clean the dishes as herezone in the upper part of portion of Y the pre-rinse. For example, a cone-shaped strucordinary temperatures is 1 receptacle 29 will be ture I99 may be suspended from the cover Ila, which is adapted to trap soapsuds around it and is so shaped that the pro-rinse does not readily v reach the soapsuds.

The detailed construction and operation of the washing machine is more fully given in my Patent No. 2,314,332 referred to hereinabove, to which reference is made, if necessary, for a more detailed understanding. Briefly stated, when the tank 34 swings upwardly to empty its contents into the receptacles 21, 28 and 29, it also seals the upper ends of the vent tubes 45 and 41 by means of the plate 49. The electric heaters preferably are constructed of spaced apart electrodes, aswill be more fully understood from the drawings and by reference to Patent No. 2,314,332. The heaters form steam in the inverted bells 29b and 29b, thus raising the level in their respective receptacles 29 and 29 to the point whre the syphons 5i! and Si operate, together with the bypass 5la which is provided for discharging the small amount of pre-rinse water from the receptacle 29.

a The original numerals from the position shown in Fig. 2 to that shown in'F'ig 1, the water. will be discharged to the receptacles 21, 28, and 29, respectively, the prewash water being preferably discharged by gravityto the washing chamber ll. Upon discharging' the washing and rising water to the receptacles 29 and 29, respectively, the heaters 53 and '55 will begin to heat the water therein. At the the motor control switch 51 within the closed by the water to start operation of the motor and likewise the switch 56 .will also be closed by the water to permit the coil 23 to become energized to effect closing of the drain valve 29. The impeller l5 will then circulate the cold or tepid pre-wash water within the washing chamber and mix it with the detergent placed therein, the circulation of the mixture in contact with the dishes being in the form of a soapy mist for a length of time serving to soak, soften and loosen the food or foreign particles adhering to the dishes, and particularly the albuminous materials which are difficult to re move when allowed to dry on the dishes. At the completion of the period of circulation of the prewash water the main supply of wash water, under the pressure of the steam generated within the receptacle 28, will be discharged to the washing chamber and mixed with the pre-wash water andcirculated in contact with the dishes to .wash the same. At about the time the washing operation is completed the rinsing water within the receptacle 29 will be forced below the switch 59 by the steam in the inverted receptacle 2917, thus de-energizing the magnet 23 for closing the drain valve; and allowing the latter to be opened by the spring 22 to ermit from the washing chamber.

At about the time this operation is completed same time the water within the receptacle 29 will be forced soapsuds and which is partially protected from used in my cope nding application Serial No. 84,504, now Patent No.

the water to discharge upwardly therein by the pressure of the steam to a level at which a small amount of pre-rinse water will discharge through the restricted bypass 5m to and through the conduit M to the washing chamber where it will be discharged in contact with the upper ends of the impeller blades at which time the impeller is still being driven by the motor. Due to the relatively small amount of pre-rinse water permitted to discharge through the by-pass 5m and its rather slow rate of discharge from the conduit M, the greater portion of the water will be acted upon by the upper ends of the blades of the impeller and thrown off by the same in a lateral direction within the lower portion of the washing chamber only, whereby to effect discharge of the soapsuds and food particles which may have accumulated therein, it being understood that at this time the drain valve is still at open position. However, since the pre-rinse water is not permitted to circulate within the upper portion of the washing chamber the soap-suds adhering to the walls thereof and to the dishes will remain thereon and be taken up by the main supply of rinse water which is discharged by the impeller to all parts of the washing chamber with the drain valve in closed position.

By the time the pre-rinse operation is completed the steam in the receptacle 29 will have raised the water to a level sufiicient to start operation of the syphon 5| which will then begin to deliver the water to the compartment 30 for passage therethrough to and through the conduits 52 and M to the washing chamber. When the water is discharged to said compartment it will close the switches 58 and 59 therein to energize magnets 23 and 60, respectively, the former for operating the drain valve to close the outlet of the washing chamber and the latter for moving the door-controlling.armature 78 from the position shown in Fig. 11 to that shown in Fig. 12 for effecting release of the latch for the door when the final rinsing operation is completed, whereby to admit air to the washing chamber to facilitate drying of the dishes therein.

Upon delivery of the main supply of rinse water to the washing chamber it will be circulated therein by the impeller at which time the soapsuds or film of soap adhering to the upper walls of the washing chamber and to the dishes will become mixed with the rinsing water and circulated therewith in contact with the dishes.

After substantially all of the rinsing water has been discharged from the receptacle 29 and the compartment 30 to the washing chamber,

the motor will continue to operate for a short period to complete the rinsing operation, the motor switch during this time being kept closed by the small amount of Water held within the upper container 64 within which the switch is disposed. The switches 58 and 59 disposed within the lower container 64, which serve to control the magnets 23 and 60, respectively, are likewise kept closed by the water therein during the completion of the rinsing period. However, as soon as the water has boiled down within the switch holding container 64, the motor will stop and the magnets become de-energized to allow the drain valve and door for th washing chamber to be automatically opened by the springs associated therewith to produce an evaporative drying action by convection flow of air thrbugh the container l3.

For convenience of description I have referred said liquid-holding zone to apply a mist of relatively cold concentrated soap wash on said dishes, thereafter adding hot water to said relatively cold concentrated soap wash to produce a relatively hot soap wash in said liquid-holding zone, whipping said relatively hot soap wash in said liquid-holding zone to apply said relatively hot soap wash to said dishes.

2. The method of washing dishes which comprises maintaining said dishes in an elevated cleansing. zone above a liquid-holding zone, whipping a soap wash in said liquid-holding zone to apply said soap wash to said dishes and to createand maintain soapsuds in said elevated cleansing zone, removing said soap wash from said liquid maintaining zone, introducing a relatively small quantity of rinse water in said liquid-holding zone and whipping said rinse water to remove a portion of soapsuds remaining on said dishes while retaining another portion of soapsuds in said elevated cleansing zone, removing said rinse water from said liquid retaining zone, introducing a, relatively large quantity of rinse water in said liquid-holding zone, whipping said last named rinse water to apply it to said dishes and to mix said retained soapsuds with said water, and thereafter evaporating adhering rinse water from said dishes to dry said dishes and to create a thin invisible film of soap on said dishes.

3. The method of washing dishes which comprises maintaining said dishes in an elevated cleansing zone, applying a soap wash to said dishes in said elevated cleansing zone to create and maintain soapsuds in said elevated cleansing zone, introducing a relatively small quantity of rinse water in said elevated cleansing zone to remove a portion of soapsuds remaining on said dishes while retaining another portion of soap suds in said elevated cleansing zone, introducing a relatively large quantity of rinse water in said elevated cleansing zone so as to mix with said retained soapsuds to produce a very dilute soapy rinse mixture, recirculating said mixture over said dishes, and thereafter evaporating adhering rinse water from said dishes to dry said dishes and to create a thin invisible film of soap on said dishes.

4. The method of washing dishes which comprises applying a relatively cool soap wash to said dishes to soak the soil on said dishes, mixlng relatively hot Water with said cool soap wash, applying said mixture to said dishes, separating the dishes from said mixture, and thereafter rinsing and drying said dishes.

ing zone by means of an amount of rinse water sufiicient to remove a portion of the soap suds and to flush out the major portion of the remaining soil while retaining a portion of the soap suds in the cleansing zone, removing said rinse water, introducing a relatively large quantity of final rinse water into said zone so as to mix with said retained soap suds to produce a very dilute soapy rinse mixture, recirculating said mixture over said dishes, and thereafter draining the final rinse water from said cleansing zone.

6. The method of washing dishes which comprises maintaining said dishes in an elevated cleansing zone, applying dishes, mixing hot water with said soap wash and applying said mixture to said dishes in said elevated cleansing zone to create and maintain soapsuds in said elevated cleansing zone, gravitationally draining away said mixture, introducing a relatively small quantity of rinse water in said elevated cleansing zone to remove a portion of soapsuds remaining on said dishes while retaining another portion of soapsuds in said elevated cleansing zone, introducing a relatively large quantity of rinse water in said elevated cleansing zone so as to mix with said retained soap suds to produce a very dilute soapy rinse a cool soap wash to said mixture, recirculating said mixture over said dishes, and thereafter evaporating adhering rinse water from said dishes to dry said dishes and to creat a thin invisible film of soap on said dishes.

7. The method of washing dishes which coinprlses applying a relatively cool concentrated soap wash to said dishes to soak the soil on said dishes, diluting said concentrated soap wash with relatively hot water and thereafter applying the mixture to said dishes so as to remove greases and other soil from said dishes.

8. The method of washing dishes which comprises maintaining said dishes in a cleansing zone, applying hot soap water to the dishes in said cleansing zone so as to loosen the soil on said dishes, removing the hot soap water from said cleansing zone, thereafter flushing out said cleansing zone by means of an amount of rinse water sufficient to remove a major portion of the remaining soil, removing said rinse water, applying a relatively large quantity of final very dilute soapy rinse water to the dishes in said zone, recirculating said final rinse water over said dishes, and thereafter draining the final rinse water from said cleansing zone.

DONALD K. FERRIS. 

